Boris Johnson has made a point of praising David Cameron as he was given a second hero's welcome at the Tory party conference in the space of 24 hours.

The Mayor of London, in a half-hour speech in Birmingham, was typically exuberant and charmed the party faithful with a light-hearted, slightly chaotic speech.

But amid continued gossip that he could become the next Tory leader, Mr Johnson also took pains to hail the "fantastic job" being done by the Prime Minister.

For a second day, the Mayor was mobbed by the media as he arrived at the conference centre and lapped up the attention.

Clearly enjoying himself, he likened the PM to a broom and Chancellor George Osborne to a dustpan as the Tories continued to clear up the mess left by Labour.

But he insisted that if he could overcome a Labour lead to win a second term as London Mayor, the Tories could fight back to win outright in 2015.

"If we can win in a recession and wipe out a 17-point Labour lead then I know that David Cameron will win in 2015, when the economy has turned round ... when people are benefiting from jobs and growth and the firm leadership you have shown and the tough decisions you have taken," he said.

The Mayor of London was mobbed again as he arrived

Wishing Mr Cameron a happy birthday, he joked: "I was pleased to see that you called me a blond-haired mop in the papers.

"If I am a mop, David Cameron, you are a broom - a broom that is clearing up the mess left by the Labour government, and a fantastic job you are doing.

"I congratulate you and your colleagues George Osborne the dustpan, Michael Gove the J-cloth, William Hague the sponge.

"It is the historic function of Conservative governments over the last 100 years to be the household implements on the floor of the house, so effective at clearing up after the Labour binge has got out of control."

In a speech studded with jokes, Mr Johnson called for the "can do" attitude of the Olympics to be applied to the economy, with British firms becoming "gold medal winners".

He spoke of the "gloom" ahead of the Games giving way to "a Ready Brek glow of happiness" once they had started, admitting this was a surprise.

Mr Johnson also praised politicians from across the party divide for their role in securing the Olympics, including his Labour predecessor and rival Ken Livingstone.

"I don't think Ken is going to come back from that one - he just got a clap from the Tory party conference, if that hasn't finished him nothing will," he joked.

Making a serious point on the economy, the Mayor said investment in training and infrastructure was vital to allowing young people to excel.

And on education, he announced plans to open up City Hall property portfolios to boost the number of free schools in London.

To cheers, he said: "I will join you in the fight to keep this country from lurching back into the grip of the two Eds - unreformed, unpunished, unrepentant about what they did to the economy and the deficit they racked up.

"We need to move forward now from the age of excess under Labour, through the age of austerity to a new age of enterprise in which we do what we did during the Olympics and build a world-beating platform for Britain, for British people and businesses to compete and win."

Mr Johnson took pains to play down his credentials to become party leader but the crowd was apparently totally in his thrall.

Outlining the capital's strengths, he listed: "We have the time zone, don't we? Yes. The right language, in fact 300 languages but we are particularly good at English and what else?"

Delegates responded: "You."

But the Mayor insisted: "No, no, no. We have the right Government in Westminster."

Following the address, Tory members appeared delighted.

John Peach, 52, from Peterborough, said: "Any message that he is trying to put across, he can do it in a common sense and humorous way that gets people's attention."